The Three Leagues is the alliance of the League of God's House, the League of the Ten Jurisdictions and the Grey League in 1471, which will lead eventually to the formation of the Swiss canton of Graubünden.

The current settlement of the Davos area started back in High Middle Ages with the immigration of Rhaeto-Romans.

Most of the lands of Graubünden had been part of the Roman province Raetia in 15 BCE.

The area later became part of the lands of the Bishopric of Chur.

A mile-high town comprising two villages, Davos-Platz and Davos-Dorf, in present Grisons canton, eastern Switzerland, it is first mentioned in written records in 1213 as Tavaus.

The barons of Vaz had allowed German-speaking Walser colonists to settle from about 1280,  and conceded them extensive self-administration rights, causing Davos to become the largest Walser settlement area in eastern Switzerland.

The League of the Ten Jurisdictions, the last of the Three Leagues founded during the Middle Ages in what is now Canton Graubünden of Switzerland, was founded in Davos in 1436.